Improvement in electro-magnetic car-brakes



J. OLMSTED. Electro-Magnetic Car Brake.

No{ 98,880. Patented Jan; 18; 1s:70.'

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UNITED STATES Josnrn OLMSTED, or KNOXVILLE, ILLINOIS.

IMPROVEMENT IN ELECTRO-MAGNETIC CAR*BRAKE$- Specification forming part of Letters Patent No. 98,880, dated January 18, 1870.

To all whom. it may concern:

Be it known that I, J osErH OLMs'rEn, of Knoxville, in the county of Knox and State oflllinois, have invented certain new and useful Improvements in Electro-Magnetic Car- Brakes, of which the following is a full, clear,

.and exact description, reference being had to the accompanying drawing making part of this specification, and in which- Figure 1 represents a plan or top view of a car-truck, partly in section, with my improvements attached; and Fig. 2, a vertical section through a portion of the same at the line a: .10 of Fig. 1

The nature of my improvements consists in dispensing with all toothed gearing as used in my invention patented April 27, 1869, and substituting therefor a simple friction-roller, whereby the friction and noise, as well as the expense of construction, are greatly lessened,

while the proper action of the brake is secured by the. direct agency of the wheels of the car or truck.

In the drawing, A is the frame of a cartruck; a a are the wheels, and A A are the axles. B is ahorizontal shaft having a hearing, b,'at one end loose" enough to allow a slight amount of lateral play to the opposite end, which has its bearing in a sliding journalbox, or, as shown in the drawing, in the end of a swinging arm, B, pivoted to the truckframe. The shaft carries a friction-roller, consisting-of a brass or copper plate, 0, flanged, as shown, and having a hub, 0, through which the shaft B passes, so as to allow the roller 0 The freedom of the end of the shaft B at the swinging arm '13, or its equivalent, permits the flanged face of the roller to be always in contact with the axle A so as to be rotated by it while the truckwh eels are revolving. The disk or friction plate D is firmly secured upon the shaft B,

near the roller (J, and carries two electro magnets, 11 d, the poles of which pass through it, and are made flush with its surface on that side which is adjacent to the roller 0, being properly insulated by plates (2 in the disk. \Vires d d connectthe coils of themagnets with a battery placed in any desired position upon the train, through the intermediatio'n of collars d upon the shaft B, which allows the same to be rotated without twisting the wires,

the general arrangement of the disk D, wires, and collars d d (1 being substantially the same as that in the brake already patented.

An armature, E, in the form of a flat circular plate, less in diameter than the roller 0, is placed loosely upon the hub c of the roller 0, being provided with pins c,which enter corresponding holes in the plate of the roller,

and thereby cause the two to rotate together,

while at the same'time end motion on the hub c is allowed to the armature E, so thatit may approach the friction-plate D and be in contact with it when the circuit is completed at the battery, and at the same time revolve with the roller 0, carrying the friction-plate Dwith it. The shaft B is connected, by a chain, f, to the upper end of the lever F, which is pivoted to the brake beam G 'of the axle A, and has its lower end connected, by a rod, f, to the brake-beam G of the axle A The brakebeams G G carry brake-shoesg of the ordinary construction.

The operation of the devices is as follows: While the train is in motion the roller (3 and armature E are rotated, by the axle A, around the shaft B, which is stationary, the electric circuit through the wires and magnets being open. When it is desired to apply the brakes the circuit is closed at the battery by means of a suitable key, and magnetismthereby de veloped in the magnets 01, by which the armature E is attracted toward and held in contact with the friction plate or disk 11). The

armature E, continuing to rotate with the roller 0, and being held in contact with the disk D, which is secured to the shaft B, imparts rotationto the latter, and, winding thereby the chain f upon it, applies the brake shoes g to the wheels a.

ing of the brake-shoes g from the wheels, and

the parts are in proper position to repeat the operation when required.

Similar devices to those herein described are attached to each truck of the train, and

The winding of the. chain f on the shaft B draws the rollerG so the wires are so connected to the magnets and battery that the circuit is opened. and closed through the whole series simultaneously, thereby enabling the brakes of the entire train to be simultaneously applied and released, enabling the speed of the train to be checked without loss of time, and greatly reducing the liability to accident;

What I claim, and desire to secure by Letters Patent, is-

1. The combination of the axle A frictionroller 0, and armature E with the frictionplate D and magnets d d of an electro-magnetic battery, arranged and operated substantially as set forth, for the purposev of causin the plate D to be held in contact with the armature E, and revolve, to be released, and remain at rest, as desired.

2% The shaftB, supported at one end by the swinging arm B or its equivalent, for the purpose set forth, and the roller 0, in combination with the chain f and lever F, substantially as shown and specified, toincrease the pressure of the roller 0 against the axle A, and prevent it from slipping while the brakes are acting on the wheels. I

3. The shaft B having lateral play at one .end, for theprirposeset forth, in combination Witnesses:

Geo. W. MCGILL, W. B. RIGHARDS. 

